Since lithium ion secondary batteries and other nonaqueous electrolyte secondary batteries are lighter in weight and have higher energy density in comparison with existing batteries, they are preferably used as high output power supplies for vehicle mounting and as so-called portable power supplies and the like.
In general, the electrodes of nonaqueous electrolyte secondary batteries are provided with a current collector and an active material layer formed on the current collector. Electrodes of such a form are fabricated by, for example, preparing a slurry for forming the active material layer, obtained by dissolving or dispersing an active material, binder and the like in a prescribed liquid medium (and including pastes and inks, and to apply similarly hereinafter), and coating the slurry onto the surface of the current collector followed by drying. Examples of prior patent literature relating to methods for fabricating an electrode include Patent Literature 1 and 2. The abstract of Patent Literature 1, for example, describes the preparation of a slurry for forming a positive electrode active material layer by kneading a positive electrode active material, an electrically conductive material and a polyvinylidene fluoride (PVdF)-based binder in a solvent (N-methyl-2-pyrrolidone) for which moisture content has been reduced to 100 ppm or less.